May 6, 1898.] 



SCIENGE. 



63& 



to the correlation of the different conceptions 

 under certain headings ('means' and 'result') 

 that I drew up the table. At the same time, I 

 recommended that Selection in the Darwinian 

 sense should be used only when the essential 

 conditions of organic progress by survival are 

 present, namely, variations* and physical hered- 

 ity. These requirements the different usages 

 of the table do fulfill ; so that as each has its 

 qualifying word ('natural,' 'sexual,' 'organic,' 

 etc.), the use of the term Selection is not am- 

 biguous. Further, in Selection of the pre-Dar- 

 winian sort, as defined by Professor Hutton, 

 whenever it is a question of organic evolution, 

 these two conditions are also requisite, i. e., 

 variation and heredity, as in Darwin's artificial 

 selection. So while I fully agree with Profes- 

 sor Hutton on the need of sharp definition of 

 Selection, I do not see the need of taking our 

 nomenclature back to pre-Darwinian zoology. 

 Moreover, the attempt would be quite futile. 

 Professor Hutton goes on to say that Dar- 

 win's term ' Natural Selection' is better than 

 ' Organic Selection.' He seems to suppose that 

 the two are used for the same thing. As the 

 proposer of ' Organic Selection ' (and all the 

 other users of the term, so far as I know, e. g., 

 Osborn, LI. Morgan, Poulton, etc., have given 

 it the same meaning) I have only to say that 

 nothing of that sort is intended. Organic Se- 

 lection is supplementary ; it is based upon and 

 presupposes Natural Selection, f It recognizes 

 the positive accommodations on the part of in- 

 dividual animals by which they keep themselves 

 alive and so have an advantage over others 

 under the operation of natural selection. I agree 

 with Professor Poulton in holding J that, so far 

 from coming to replace natural selection or im- 

 pair our confidence in it, it does quite the re- 

 verse. And I also think that it explains phe- 

 nomena of 'determinate evolution' which are not 

 fully explained by natural selection alone. So 

 some such new term is justified ; and it is really a 



*I there said natural selection and physical he- 

 redity, but the first requisite is really the supply of 

 variations. 



t See my papers in the American Naturalist, June, 

 July, 1896. 



t Science, October 15, 1897, and Nature, April 14, 

 1898, p. 556. 



form of ' selection' in the Darwinian sense, for 

 it requires both variations and physical heredity. 

 Moreover, it is contrasted with natural selec- 

 tion on a point of which Professor Hutton 

 speaks. He says: "Natural Selection is not 

 truly selection, for the individuals can hardly 

 be said to select themselves by their superior 

 strength, cunning, or what not." Now, 'or- 

 ganic selection' supposes them doing this, in an 

 important sense. It is a sort of artificial selec- 

 tion put in the hands of the animal himself — that 

 is, so far as the results go. 



As to ' isolation' (Professor Hutton's other 

 topic), it is certainly important, but is Professor 

 Hutton right in considering it a positive cause ? 

 He says : "It is isolation which produces the 

 new race ; selection merely determines the di- 

 rection the new race is to take," and "isola- 

 tion is capable of originating new species." 

 But how '? Suppose we isolate some senile ani- 

 mals, or some physiological minors, will a new 

 race arise ? The real cause in it all is repro- 

 duction, heredity with its likenesses and its 

 variations. Both isolation and natural selec- 

 tion are negative conditions : what are called in 

 physical science ' control' conditions, of the 

 operation of heredity. So in seeking out such 

 principles as ' selection,' 'isolation,' etc.,weare 

 asking how heredity has been controlled, di- 

 rected, diverted, in this direction or that. Iso- 

 lation is as purely negative as is natural selec- 

 tion. Any influence which throws this and 

 that mate together in so far isolates them from 

 others, as I have said in a notice of Romanes' 

 and Gulick's doctrine of isolation, * and inas- 

 much as cei'tain of these control conditions 

 have already been discovered and otherwise 

 named by their discoverer as ' natural selec- 

 tion,' 'artificial selection,' 'sexual selection,' 

 etc. , it is both unnecessary and unwise to at- 

 tempt now to call them all 'isolation.' For if 

 everything is isolation then we have to call each 

 case by its special name, just the same, to dis- 

 tinguish it from others. 



There remains the question as to whether 

 isolation, in the broad sense of the restriction 

 of pairing to members of a group, can result 

 in specific differences without any help from 

 ' selection' of any kind. If that should be 



* Psychological Review, March, 1898, p. 216. 



